Obesity Impairs Academic Attainment In Adolescence

A new study by Strathclyde, Dundee, Georgia and Bristol universities suggests obesity in adolescent girls is associated with lower academic results during their teenage years.

The results of the study suggest that girls who were obese, as measured by BMI (body mass index) at age 11, had lower academic attainment at 11, 13 and 16 years when compared to those of a healthy weight.

Attainment in the core subjects of English, Maths and Science for obese girls was lower by an amount equivalent to a D instead of a C, which was the average in the sample.

The present study suggests that adolescent obesity in the UK in the 2000’s had an adverse impact on subsequent academic attainment in girls. Moreover, this adverse impact was robust to confounding variables, and was almost certainly of practical significance as it was sufficient to cross grade boundaries in attainment. That is, for females, after controlling for a wide range of confounders, being obese at 11 predicted
lower attainment by one third of a grade at age 16.

This would be sufficient to lower average attainment to a grade D instead of a grade C.

Furthermore, examination of change in weight status found that females who were overweight or obese over the long term had lower attainment that those who were of a stable healthy weight. Being overweight or obese at age 16 was not as detrimental for attainment if participants had been a healthy weight at age 11 suggesting that potentially, it is long term overweight/obesity that is the most problematic.

The present study provides clear support for the hypothesis that obesity is independently associated with poorer academic outcomes in adolescence. This result was robust in females and while there was a trend for similar results in males, they were not as convincing.

Impairments in academic outcomes in high school observed in the present study may at least partly explain decrements in adult educational attainment and income associated with adolescent obesity found in two older studies from the US and UK.

The association between obesity and impaired academic attainment may be explained by a range of plausible impacts of adolescent obesity on: physical and mental ill health and consequent absenteeism from school; ‘indirect effects’ on teacher grades; evidence is also emerging for more direct mechanisms linking excess child or adolescent adiposity and/or the lifestyles associated with it, to impaired cognition.

John Reilly, professor of physical activity and public health science at Strathclyde University and the lead investigator of the study, said: "Further work is needed to understand why obesity is negatively related to academic attainment, but it is clear that teenagers, parents, and policymakers in education and public health should be aware of the lifelong educational and economic impact of obesity."